This character is a Other Symbol and is commonly used, that is, in no specific script.
The glyph is not a composition. Its East Asian Width is wide. In bidirectional text it acts as Other Neutral. When changing direction it is not mirrored. U+1F600 offers a line break opportunity at its position, except in some numeric contexts.
The CLDR project calls this character βgrinning faceβ for use in screen reading software. It assigns these additional labels, e.g. for search in emoji pickers: cheerful, cheery, face, grin, grinning, happy, laugh, nice, smile, smiling, teeth.
This character is designated as an emoji. It will be rendered as colorful emoji on conforming platforms. To reduce it to a monochrome character, you can combine it with Variation Selector-15: ποΈ See the Emojipedia for more details on this characterβs emoji properties.
On Youtube this character is sometimes wrongly displayed as U0001f600.
The Wikipedia has the following information about this codepoint:
A smile is a facial expression formed primarily by flexing the muscles at the sides of the mouth. Some smiles include a contraction of the muscles at the corner of the eyes, an action known as a Duchenne smile.
Among humans, a smile expresses delight, sociability, happiness, joy, or amusement. It is distinct from a similar but usually involuntary expression of anxiety known as a grimace. Although cross-cultural studies have shown that smiling is a means of communication throughout the world, there are large differences among different cultures, religions, and societies, with some using smiles to convey confusion, embarrassment or awkwardness.